Grinding machinery



June 14, 1932. J. E. cAsTER GMNDING MACHINERY s sheets-sheet 1 Filedsept. 2s. 192e GRlNl/vo JNDEXER-MUY/NG BACK *BACK-E AL L 6 June 14,1932. J. E. cAsTER GRINDING MACHINERY Filed Sept. 23. 1926 5Sheets-Sheet 2 anoz "eq J. E. cAsTER 1,862,882

GRIHDING MACHINERY Filed Sept. 23. 1926 3 Sheets-Sheet 3 UNITED STATES IAUI IIIIIUI PATENT OFFICE JOHN E. CASTER, OF CINCINNATI, OHIO, ASSIGNORTO THE CINCINNATI GRINDERS, INCORPORATED, OF CINCINNATI, OHIO, ACORPORATION OF OHIO GRINDING MACHINERY Application led September 23,1926. Serial No. 137,205.

This invention relates to improvements in grinding machinery and hasparticular reterence to a novel and improved mechanism especiallydesigned for use in the grinding of spherical articles such as balls forball bearings.

Prior to the present invention it has been customary to produce balls bya lapping type of mechanism in which the balls Were fed for examplebetween a pair of high speed members intended to jointly eii'ect slightabrasion of the several surface portions of the ball, coupled with ahigh spinning action tending to produce the spherical form thereof. Thisapparatus in commercial use has been elaborate ot structure and slow inoperation.

As distinguished from such mechanisms ot the prior art. it is thepurpose ot the present invention to provide a novel and improvedstructure for rapidly producing spherical articles b v a true grindingprocess, capable of receiving rough forged or molded balls for exampleand by maximum grinding and stock removal in minimum time to' reducethese rough globules to true spherical form of desired accuracy Withinlimits of less than a thousandth part of an inch.

A further object ot the invention is the provision of a mechanism forthe grinding of balls which Will positively and definitely regulate andcontrol the rotative action of the blanks during grinding.

A further object of the invention is the provision of a mechanism whichWill overcome diiiiculties due to dependence on a single grindingsurface tor reducingr the initial stock the prescribed amount and whichwill consecutively present a plurality of formed surfaces to the blankto gradually reduce same to its final accurate dimensions, thusprolonging the lift of the grinding surface as a Whole.

Another object of the invention is the provision of a mechanism Whichshall balance and distribute the Wear on the several portions of aformed grinding Wheel to aid in the maintenance of the proper operativesurface thereon.

An additional object of the present invention is the provision of agrinding machine in which the progress of the work through the machineshall be ositively controlled and the Work itselt` detpinitely supportedin predetermined position Within the machine at all times duringoperation thereon.

Other objects and advantages of the present invention should be readilyapparent by reference to the following specification taken in connectionwith the accompanying drawings and it will be understood that anymodiications may be made in the specific structural details hereillustrated Within the scope of the appended claims Without departingfrom or exceeding the spirit of the invention.

Figure 1 is an elevation of a machine embodying the invention.

Figure 2 is a vertical section through the Work controlling mechanismtaken on line 2 2 of Figure 1.

Figure 3 is a diagrammatic view of the movement of the work controllingmember.

Figure 4 is a fragmentary view similar to Figure 2, illustrating theshifting member in raised position.

Figure 5 is a detail of the cam and drive mechanism with cover plateremoved.

Figure 6 is a sectional View on the line 6-6 of Figure 5, parts beingshown in elevation.

Figure 7 is a vertical sectional vieW on the line 7--7 of Figure 2.

Figure 8 is a fragmentary transverse section on the line 8-8 of Figure2.

Figure 9 is a detail of the Work delivery chute, and,

Figure 10 is a fragmentary view illustrating the regulating Wheeloscillating mechanism.

In carrying out the present invention as illustrated in the drawings,use has been made of a commercial type centerless grinder including'fabed or base A having mounted thereon a grinding wheel B and a slide C.The in and out position of slide C is controlled through screw D andassociate mechanism hereinafter described. Transverscly movable on slideC is a second slide E which bears the angularly adjustable regulatingwheel F. Transverse sliding movement may be imparted to the regulatingwheel as by forming its spindle 15 with an extension bearing cam 16 inengagement with roller 1T on bracket- 18 of slide C. As a result it willbe understood that as the regulating wheel F is rotated theinterengagement of cam and roller will cause a transverse reciprocatingmovement of the wheel for a purpose to be hereinafter described.

Suitably supported on the "bed A is the work rest bracket 19 having atits upper edge the angle top work rest blade 20. This blade as shown inFigure 8 has a corrugated edge providing the work rest portions 21 whichlit into the several grooves 22 annularly disposed on the periphery ofgrinding wheel B.

In the operation of the machine work pieces are fed downward throughtube 23 against the work stop 2l carried by the bracket 19 and thenceintroduced into the first of the series of grooves 22. When sointroduced the work piece 25 lies on top of the work rest blade 2O andprojects to a greater or less degree into the adjacent groove 22 of thegrinding wheel,

while it is backed up on the opposite side by the regulating wheel F.The wheel B is rotated downwardly toward the rest at a high grindingrate of speed. while the wheel F is slowly rotated upwardly and servesto grip and rotate the work. In this connection the oscillation of theregulating wheel is of particular value. If the regulating Wheel had itsaxis parallel with that of the grinding wheel the combined action of thegrinding and regulating wheels would tend to rotate the ball beingoperated upon but without a universal spinning movement. Also, if theregulating wheel were merely thrown to a slight angle as is most clearlyindicated in Figure 10 for example, there would then be a combinedthrust component exerted by the regulating wheel..l tending to rot-atethe ball about a horizontal axis and also exerting a diagonal componenttending to twist the ball around. This combined action it has been foundwill produce satisfactory ball grinding in that the combined thrustcomponent being really that of a spiral insures a constant presentationof fresh points on the ball periphery to the operative portion of thegroove of the grinding wheel with the result that a perfectly round ballmay be produced. It has, however, the objection that the thrust due toangle is constantly in one direction or against the rear side of thegrooves, tending to break down the grooves in the grinding i a wheel. Itwill be understood that the efficient operation of the machine may becontinued r only so long as the grinding wheel grooves retainapproximately their proper shape. T o counter-act this uni-lateralbreaking down of the grinding wheel the reciprocation of the regulatingwheel is contemplated. This causes the lateral thrust component of theregulating wheel to be exerted first toward one side of the grindingwheel groove and then toward the other, thus more evenly distributingthe wear and prolonging the operative life of the individual grooves.

In order that the maximum production may be secured from the machine, itis desirable to utilize as wide a grinding wheel as possible, thusproviding a. number of grooves for simultaneous action on diderentballs. To enable the balls to be inserted within and removed from thegrooves, utilization is made of the principle of varying the width ofgrinding throat as determined by the grinding and regulating wheels. Themechanism for this includes the link 26 coupled with screw D and the cam27 driven through worm 28 and motor 29, the timing of the parts beingsuch that the cam gradually shifts the regulating wheel in toward thegrinding wheel to first close up the throat on the work, then place workagainst grinding wheel until desired amount of stock has been removedafter which throat is then opened up to disengage the work.

In view of the fact that the work pieces as taken to the machine arefrequently quite irregular in form, if the entire grinding operation isperformed on the rough blank by a single groove there is a greattendency towards slightly breaking down the surface of the groove, thuscausing a variation in size of the finished work. To overcome thisdifliculty the machine is constructed to automatically advance the workpieces from groove to groove, the first groove taking the heaviest cutand the last the lightest, so that in this way a single truing of thegrooved wheel will serve to produce a. maximum number of accuratelysized work pieces. To cause the step by step movement of the work piecesalong the work rest and at the same time to discharge the completed worknieces and introduce new work pieces at the entrance end of the machine,use is made of a carrier member 30 having a. plurality of notches 31corresponding in number to the grooves on the grinding wheel. Thismember has depending arms 32 engaged by guides 33 and 34 which permit ofits consecutive cycle shifting in vertical and horizontal directions asdiagrammatically indicated in Figure 3. These movements are eifected bythe double cam 35-36 on cam shaft 37, driven as by chain 38 and pulley39 from shaft 40. This shaft is driven through spur gearing 41 and bevelgears 42-43 from shaft 44 of cam 27. The movement of the carrier is thustied in with the canrcontrolled in and out movement of the regulatingwheel, so that it shifts at predetermined variations in the width ofgrinding throat, taking its initial movement which may be considered avertical movement downward into engagement with the series of rolls onthe work rest and with the front terminal roll which is resting againststop 24. This takes place as the regulating wheel is moving outwardly toopen up the grinding throat. The next movement is a transverse slidingmoving in which the balls or work pieces are all shifted the amount ofwidth of one groove and separating wall rearwardly along the work rest.At this point there is a pause for the shifting plate to steady theballs until the regulating wheel moves in sufficiently to pass them backinto their respective grooves. The parts are then in the positionillustrated in Figure 2. From this position continued rotation of thecam 35 causes it to engage pin 41 lifting the carrier slide upward outof engagement with the work pieces as is shown in Figure 4. Theregulating wheel has then pressed the balls firmly into the grooves ofthe grinding wheel for operation thereby. As the grinding continues thecarrier slide moves back to the' left in position to be brought downwardand again engage and shift the series of balls. As shifted the finalcompleted ball is carried away by discharge trough such as 45.

It will be understood that the lateral shifting movement is imparted bythe interengagement of cam 36 with the two members 33 as should be clearby reference to Figure 2 of the drawings. It will also be understoodthat a specifically different mechanism may be utilized for impartingthe transverse movement to the balls if desired to use the step by stepreduction with a single wheel or that the mechanism may be utilized forsingle simultaneous grinding of a multiplicity of balls` depending oneach groove for finishing its individual ball if preferred. In eitherevent, however, the relative transverse movement to cause a diagonal orlateral thrust against first one side of the grinding wheel groove andthen the other is particularly desirable and efficient. It is also to beunderstood that while the manner of obtaining this diagonal thrust hasbeen shown as that of imparting transverse reciprocating movement to theregulating wheel during the grinding operation, that it is possible toobtain a similar result by reciprocating either the grinding wheel orthe work rest on which the balls are frictionally held by the pressureof the grinding wheel and that broadly speaking I consider these threeas mechanical equivalent structures in that similar results may beobtained by them, although for simplicity of operation in connectionwith the shifting carrier and other parts I have found reciprocation ofthe regulating wheel the more desirable.

I claim l. A grinding machine including opposed grinding and regulatingwheels and an intermediate work rest, the grinding wheel moving in thedirection of the work rest at a high or grinding rate of speed and theregulating wheel having its operative surface moving upwardly adjacentthe work rest at a speed to frictionally engage and control the rate ofrotation of the work piece, the grinding wheel having a work receivinggroove formed annularly in its face and means for reciprocating one ofthe three work throat forming members to alternately urge the work pieceagainst opposite sides of the grinding wheel groove to equalize the wearon the walls of the groove.

2. A grinding machine including opposed grinding and regulating wheelsand an intermediate work rest, the grinding wheel having its operativesurface moving toward the Work rest at a high rate of speed and theregulating wheel having its operative surface moving upwardly asrespects the work rest at a slow or regulating rate of speed and meansfor causing one of the first named parts to exert a lateral thrustcomponent on the work piece, producing a twisting movement of the workpiece on the Work support, the grinding wheel having work piece engaginggrooves preventing lateral displacement of the work pieces under theinfluence of said thrust component.

3. A grinding machine including opposed grinding and regulating wheelsforming a work receiving throat therebetween, the grinding wheel havinggrooves in its face complementary to those to be produced on a workpiece, means for alternately opening and closing the work receivingthroat, and means for automatically advancing the work piece in a stepby step movement as the throat is alternately opened and closed.

4. A grinding machine including a grinding wheel having a groovedperipheral face, means opposed to the grinding wheel for engaging thework and imparting a twisting movement thereto as respects the groovedface of the grinding wheel and means for supporting the work piece inthe throat between the grinding and regulating wheels, said worksupporting means being disposed in position to take up the thrust of therotating grinding wheel whereby the combined effect of the grindingwheel grooves and work rest limit the bodily displacement of the worktended to be imparted thereto by the grinding wheel and its opposedmember.

5. A centerless grinding machine including a work rest, a grinding wheeldisposed at one side of the work rest and operable at a high grindingrate of speed with its adjaummm( cent surface moving in the direction ofthe work rest to urge work pieces thereagainst, a regulating wheeldisposed on the opposite side ofthe work rest with its operative surfacemoving upward relative thereto and rotatable at a slow rate of speed tocontrol the rate of rotation of the work, means providingr definitestations for the individual work pieces during grinding, and means forpositively shifting the work from station to station.

6. A centerless grinding machine of the character described including agrinding wheel operable at a high grinding rate of speed and an opposedregulating wheel operable at a slow controlling rate of speed to controlthe peripheral presentation of the work to the grinding wheel, a. workrest disposed intermediate said parts for supporting work for thecombined grinding and controlling actions of said wheels thereon, andautO- matic means for positively imparting predetermined increments ofmovement longitudinally of the work rest to work pieces wherebv the worknieces are intermittently shifted from entrance to discharge termini ofthe grinding throat between the said wheels.

7. A centerless grinding machine of the cha acter described including agrinding wheel operable at a high grinding rate 0f speed and an opposedregulating wheel operable at a slow controlling rate of speed, a workrest disposed intermediate said parts for supporting work for thecombined grinding and controlling actions of said wheels thereon, anautomatic means for positively imparting predetermined increments 0fmovement longitudinally of the work rest to work pieces whereby the workpieces are intermittently shifted from entrance to discharge termini ofthe grinding throat between the said wheels, said means having portionsfor holding individual work pieces in predetermined spaced relationduring said shifting movement.

8. A centerless grinding machine for the production of contouredarticles including a grinding wheel operable at a high rate of `speedhaving a contoured surface adapted for simultaneous engagement with aplurality of work pieces, a work rest for supporting said work piecesand an opposed slowly operable regulating wheel for controlling the rateof rotation of the work pieces, and intermittently operable meansengageable with the work pieces for transferring the work pieces inpredetermined spaced relation from one to another of the contoured workengaging portions of the grinding wheel.

9. A centerless grinding machine for the production of contouredarticles including a grinding wheel operable at a high rate of speedhaving a contoured surface adapted for simultaneous engagement with aplurality of work pieces, a work rest for supporting said work piecesand an opposed slowly ops erable regulating wheel for controlling the;

rate of rotation of the work pieces, intermittently operable meansengageable with the work pieces for transferring the work pieces inpredetermined spaced relation from one to another of the contoured workengaging portions of the grinding wheel, and means for automaticallysupplying additional work pieces to the transfer mechanism.

l0. A grinding machine for simultaneous operation on a plurality ofcontoured work pieces including a grinding wheel having a plurality ofdistinct contoured work engaging portions, an opposed regulating wheelfor controlling the rotation of said work pieces, a work restintermediate the grinding and regulating wheels in the work engagingthroat formed thereby, and a comb member disposed in opposition to thework rest for simultaneous engagement with a plurality of work piecesand means for shifting the comb when in engagement with the work pieceswhereby the work pieces may be transferred from one to another of thecontoured portions of the grinding wheel in proper spaced relation.

11. A machine for the production of balls 0r other contoured articlesincluding a contoured high speed grinding wheel and an opposed slowspeed work controlling wheel forming a grinding throat therebetween, awork support-ing rest projecting within the grinding throat, means forvarying the width of grinding throat, and means for shifting individualwork pieces transversely of the grinding throat when the same is 0fincreased width comprising a work transferring member having portionsfor engaging and retaining individual work pieces in predeterminedspaced relation, and means for laterally shifting the work engagingmember while the work pieces are so held.

12. A machine for the production of balls or other contoured articlesincluding a contoured high speed grinding wheel and an 0pposed slowspeed work controlling wheel forming a grinding throat therebetween, awork supporting rest projecting within the grinding throat, means forvarying the width of grinding throat, and means for shifting individualwork pieces transversely of the grinding throat when the same is ofincreased width comprising a work transferring member having portionsfor engaging and retaining individual work pieces in predeterminedspaced relation, means for laterally shifting the work engaging memberwhile the work pieces are so held` means for disengaging the workshifting member from the work pieces, and for returning same to workre-engaging position.

13. The combination with a centerless grinder including opposed grindingand regulating wheels and an intermediate work JOHN E. CASTER.

